The invention belongs to the technical field of time-
frequency characteristic detection of non-stationary signals, and provides a time-
frequency analysis method of non-stationary signals, which comprises the following steps: S1, designing a damping forced vibration
function group, and according to a frequency range and
frequency resolution precision required to be detected by a to-be-analyzed non-stationary
signal, calculating a time-
frequency characteristic of the to-be-analyzed non-stationary
signal according to the frequency range and
frequency resolution precision required to be detected by the to-be-analyzed non-stationary
signal; determining the number of functions in the
function group and the resonant frequency of each function; s2, converting the damped forced vibration
function group into a difference equation for numerical calculation; according to the method, a group of damped forced vibration functions is designed, and the resonant frequency, the damping coefficient and the
damping function of each function in the function group are set according to the actual demand of the to-be-analyzed signal, so that the time-frequency characteristics of the non-stationary signal can be accurately analyzed; in addition, the
frequency resolution precision of the method is determined by the set number of functions, can be flexibly adjusted according to requirements, can be infinitely increased to improve the precision, and can also be reduced by only analyzing important frequency bands.